The present invention relates to compositions which are useful to at least partially correct an effect of ametropia in a mammalian eye, to methods for at least partially correcting such an effect of ametropia, and to methods for producing such compositions. More particularly, the present invention relates to a plurality of holographic particles, which are preferably administered to the mammalian eye in combination with a carrier component, which are effective, when in proximity to the cornea of the eye, to at least partially correct an effect of ametropia in the eye.
Contact lenses are very effective in correcting effects of ametropia in the eye. Ametropia is a generic term which refers to any condition of imperfect refraction of the eyes, such as nearsightedness, farsightedness or astigmatism.
One disadvantage of conventional contact lenses, whether hard contact lenses or soft contact lenses, is that certain wearers at least perceive a degree of discomfort when the lenses are being worn. In addition, contact lenses can be difficult for certain people to insert in and remove from the eye. Further, conventional contact lenses, when removed from the eye, are susceptible to being misplaced or lost.
The use of holographic lenses has been suggested, for example, in conventional spectacles or glasses (Georgaras et al U.S. Pat. No. 5,235,441) and in a contact lens or implant lens (Freeman U.S. Pat. No. 4,641,934). In these previous embodiments, a single holographic element is used in the lens.
It would be advantageous to provide a system not requiring either conventional spectacles or contact lenses for correcting one or more effects of ametropia in a human or animal eye.